The right air pressure

[sasik]

I have a quick question

The air pressure in the expansion tank of a new combi boiler is preset for 1.5bar.
I filled the system with water up to 2bar.

My question is, what will be the correct air pressure in the tank now after I filled the system with water? should it be 1.5bar or should it be higher?

Thanks sasi

 

[Deleted member 2053]

It should tell you in the installation instructions. It depends a bit on the height of the house and the relative position of the boiler but I generally set the ones I install to about 1 bar.

 

[sasik]

Hi grahamep

Thanks for your reply, maybe I should make my question moor clear. the air pressure and the water pressure are all set as they should,no problem there.
All I want to know is if you took a reading of the air pressure when the system is running will it register higher then the preset pressure. It is not a question of right are wrong, I just want to know if the air pressure in the vassell increase.

Thanks sasi

 

[Mike Jackson]

The pressure will equalise either side of the diaphragm so the pressure in the vessel would read the same as the system pressure gauge.

Mike

 

[sasik]

Hi Mike

Thank you very much for clearing it out.

sasi

 

[Deleted member 2053]

Sorry I misread. Mike's answer is correct. Not that he needs me to affirm that!